The present invention relates to industrial controllers for the real-time control of equipment used in manufacturing and in particular to an industrial controller that automatically organizes equipment for the manufacture of a products based on the capabilities of the equipment.
Industrial controllers are special purpose computers used in controlling industrial processes. Under the direction of a stored control program, an industrial controller examines a series of inputs reflecting the status of the controlled process and changes a series of outputs controlling the industrial process. The inputs and outputs may be binary, that is, on or off, or analog, providing a value within a continuous range. The inputs may be obtained from sensors attached to the controlled equipment and the outputs may be signals to actuators on the controlled equipment.
Unlike the standardized software normally executed on conventional computers, the control program executed on an industrial controller is normally unique to each controlled process. The writing and troubleshooting of the control program is thus a significant cost in the creation of an industrial control system. After the controlled program is complete, it must often be modified as the product to be manufactured changes or as equipment is exchanged, replaced or repaired.
The above referenced parent to this application describes a self-configuring industrial control system employing a number of autonomous control units, each associated with a particular piece of manufacturing equipment. The autonomous control units are programmed with data describing the capabilities of their equipment and the equipment's ability to interact with other equipment. A desired product is described in a "job description language" and broadcast to the autonomous control units, each which identifies portions of the job that they can complete. The autonomous control units then exchange bids and counterbids with the other autonomous control units to allocate the job among units and to select the desired operating parameters of the associated equipment. The autonomous control units are programmed with generalized goals so that the allocation may be further optimized for high productivity, low cost or some other objective measure.
The bidding process accommodates competing goals of the different pieces of equipment. Nevertheless, this bidding process can be quite time consuming and in certain instances, can disproportionately allocate resources to downstream equipment whose counterbids drive the ultimate job plan produced.